Geo  l  smith



@glatten glatte @anni @ffice GEORGE L. SMITH, OF BROOKLYN, NEW YORK. 'p

Letters Patent No. 69,134, dated September 24, 1867.

CIRCULAR GRATE FOR IUBNAGES.

lO ALL WI-IOM ll MAY` CONCERN:

Be it known that I, GEORGE' L. Samui, ef Brooklyn, in the countyof Kings, and State of New York, have in rented a Circular Grate for Furnaces; and I do hereby decla-re the following to be a full, clear, and exact description thereof, reference being had .to the accompanying drawings, making part of this specification, in whieh- Figure 1 is a plan view of'cne-half of the circular grate.

Figure 2 is a diametrical section through the grate.

Figure 3 is a View of the outer eudoi Athe grate-segments or. sections.

Similar letters of reference indicate corresponding parts in the several figures.

The object of this invention is to` produce a circular grate for. the circular furnaces f upright boilers, in suoli manner that every har and part composing the grate shall have freedom to expand and contract,thereby preventing a warping or sagging of the bars of the grate or framethereof, and consequent rapid destruction of the grate. Another Objectis to provide for removing and renewing 'any one or more of the sections composing the grate when one or more of thc sections become useless from long use; also to provide a central independent support for the sections ot' the grate, which is so constructed as to prevent a. depression or sinking of the ccntral portion thereof, all as will be hereinafter explained.

To enable others skilled in the art to understand my invention I will describe its construction and operation.

In the accompanying drawings I have represented a circular grate, which is elevated in the centre so that its surface inclincs from the centre to the circumference7 but, if desired, this grate may be made with its surface l'lat, so that the top surfaces of all the sections ot` which it is composed will all be in the same plane. The grate is composed of a number of segments, B B, surrounding a circular-grated section, A, which latter forms the central pieceof the grate, as shown in iigs. 1 and 2. The central piece A, and also the inner ends of the surrounding segments B, are supported upon the acute edges of double-bevelled bars C D, or what are termed V bearers. This central support is mounted upon a pedestal, E, and constructed with radial ribs united at their outer ends to the circular bearer, so as to allord a iiim support for preventing the central portion of the grate from sagging, and at the same time to allow of a free upward passage of air. The' central circular-grate section A isl constructed of one or more concentric rings, united by intermediate radial ribs, as shown in the drawings, tig. 1. The sections B B surrounding this central section are each composed Yof radial side bars, united by a number of curved ribs or bars, 132, which are concentric to the axis of the centre-piece A. lThese concentric ribs Bz arcarranged at regular intervals apart, and the longest ones, which are nearest the circumference of thc grate, are strengthened by intermediate ribs uniting the former in pairs, as shown. The lower edges of the concentric ribs of the segments B are arched, asfclearly shown in the outer end view, fig. 3, of one segment, for the twofold purpose ot' weakening the casting at the middle of its width, or in the middle of Leach one of the-concentricbars or ribs, so that expansion will more readily centre at such point, and thus relieve any tendency to strain and spread the segment 'by intense heat. The arched bars allow of a free circulation of air over the bearer C, and also allow the ashes which would otherwise clog between theouter ends of the segments and the boiler F, to pass freely through or between said bars to the ash-pit. In vthe'vertical cross-section, lig. 1, it will be seen that the central section A is supported upon the V-shap'ed bearers or arms'D of the circular bearer O, and that the inner ends ofthe side bars of the surrounding segments B are notched over this circular hearer,' so as to bc held in place against endwise displacement. The outer ends of these segments are vsupported upon the masonry at the buse of the furnace, so as to allow of any longitudinal expansion which will take place.

I am aware that it is not new in circular furnaces to employ circular grates composed of separate sections, as an instance of this hind'will'bc found in the upright Corlis Boiler, and I am also aware that rectangular grate surfaces have been composed of a number of rectangular sections supported upon V bearers, and these contrivances I do not claim as my invention.A I have so constructed a circular grate, of independent segments or sections surrounding a central circular section, that the air-openings or spaces between the ribs of each section.

will always be preserved of a uniform size, and the strain and hitherto inliurious results of expansion of gratas are in my gratc'entirely prevented.

Hnvng`-described my invefnf'on, what I claim as new, 1. The construction of a enulm"y grate of 4tion, A, substantially :as described.

2. The construction 0f t'he segmnts B, with coneentriq and arched cross-burgz, sub-stwniully-us described. 4

3. An independent central support for the v sction'g and 'segments B of' :L circular grate, onstructed substantially as dscri-bed and desire to secure by Lete'rs`Pa-tent, is#- a, series of segments or sectians, B, surrounding a conti-.1I sac- GED. L. QMIIIL Witessees i Cms. E. Fmslr, Ch l?. PALMER. 

